README

The table provides a summary of the information in CCSM timing files. The
raw timing files are generally available via a link in the CS/Mode column.
Lots of detail information is available in the raw timing file like
run length, a copy of env_conf, and other things.

Generally, "best" load balanced configurations are presented in the table.
Please feel free to forward timing files for cases that aren't currently
available and we'll put those up on the site. If you find configurations
that perform better (in cost, throughput, or both) than what's on the table,
please send us those results as well.

The README is divided in two further sections. The first section
provides a summary of the table. The second section provides a
discussion of output found in the raw timing table.

Table README:

A summary of the table columns follows:

Machine - Name of the hardware that ran the case

Resolution - Grid that the case used

CSet/Mode - Component Set and any information about the mode. B is all
active and A is all data. See the CCSM Users Guide for more information
about the component sets. See also the env_conf at the bottom of the raw
timing file for more detailed information.

Total PEs - total number of pes used for the run. This is the sum of
the atm, lnd, ocn, ice, and cpl pes.

Cost - the cost in pe-hrs for this case to run one
simulated year. Lower cost is better.

Thru-Put - the number of years of simulation that could
be produced if the model ran continuously for one day.

component pes - Five columns, one for each component, summarizing
the number of pes used. The information there is total pes, mpi tasks
x omp threads, root pe : pe stride.

Raw Timing File README:

A section of the README for the Timing Tool is provided next.

CCSM TIMING PROFILE

The first section summarizes the case analyzed. This information is
extracted from the environment and the case setup at the time the
timing tool is invoked. Most of the output in this section is
straightforward.

"lid" is the timestamp associated with the ccsm run and is part
of the filename for the ccsm log files.

"date" is the timestamp at the time the timing tool was run.

A summary of the components and their pes is provided. Generally,
the pes set in CCSM are expressed as the number of MPI Tasks
by the number of OpenMP Threads (MPI x OpenMP). The total
is the product of these two numbers.

ANALYSIS

This section provides an overview of the CCSM timing and contains a
summary of several critical regions in CCSM. The source of these
numbers is described below in the details section. Users are
encouraged to review the load balance chart to verify the comparisons
provided below are applicable. Letters (ie. E+F) reference sections
in the load balance chart.

1. Overall Metrics

Model Throughput is the number of years of simulation that could
be produced if the model ran continuously for one day.

Model Cost is the cost in pe-hrs for this case to run one
simulated year. Lower cost is better.

DETAILS

CCSM is a complex system. Four tightly coupled physical components are
running sequentially and/or concurrently. They communicate via the fifth
component, the coupler (or driver). The communication pattern is largely
set by science requirements.

env_conf

Appended at the end of each timing file is a copy of the
case env_conf file. This generally provides addition insights
into various modes or other physics that might have been
turned on during the run. These can have a large bearing
on the timing of a run.